P-hydroxymethylphenylacetamidocephalosporins

ABSTRACT

7-(p-Hydroxymethylphenylglycylamido)cephalosporins are prepared by acylating a 7-aminocephalosporin compound. The products have antibacterial activity.

This is a division of application Ser. No. 359,566 filed May 11, 1973now U.S. Pat. No. 389,634 which is a continuation-in-part of applicationSer. No. 262,903, filed June 14, 1972, now U.S. Pat. No. 3,867,380,which was a continuation-in-part of Ser. No. 116,589, filed Feb. 18,1971, now abandoned, which was a continuation-in-part of Ser. No.99,296, filed Dec. 17, 1970, now abandoned, and it is also acontinuation-in-part of application Ser. No. 289,499, filed Sept. 15,1972, now U.S. Pat. No. 3,855,213, which was a continuation-in-part ofSer. No. 262,903, filed June 14, 1972 and of Ser. No. 116,599, filedFeb. 18, 1971, now abandoned, which latter application was acontinuation-in-part of Ser. No. 99,296, filed Dec. 17, 1970, nowabandoned.

This invention relates to cephalosporin compounds. In particular, theinvention relates to p-hydroxymethylphenylacetamidocephalosporins offormula I ##SPC1##

wherein A is acetoxy, hydrogen, methoxy, methylthio, or monocyclicheterocyclic thio.

The invention also relates to a process for preparing the compounds offormula I comprising acylating a compound of the formula ##SPC2##

Wherein A is as defined above, with p-hydroxymethylphenylglycine, or anacylating or activated derivative thereof, the amino group beingprotected with an easily removable protecting group.

The invention also relates to intermediates for preparing the compoundsof formula I, these intermediates being p-hydroxymethylphenylglycine andits N-t-butoxycarbonyl derivative.

Among the preferred compounds of the invention are those of formula I inwhich A is heterocyclic thio. Such preferred heterocyclic groups include1,2,3-triazol-5-yl, 2-methyl-1,3,4-thiadiazol-5-yl, and1-methyltetrazol-5-yl. Other such groups can be oxadiazolyl,1,2,4-triazol-3-yl, and tetrazol-5-yl and methyl derivatives thereof.The term heterocyclic, however, is intended to represent any monocyclicheterocyclic group containing, in addition to one or more carbon atoms,one or more nitrogen, sulfur, or oxygen atoms and being eitherunsubstituted or substituted with one or more lower alkyl or alkoxygroups of one to four carbon atoms.

The product compounds of the invention are prepared by acylating the7-amino group of a compound of formula II withp-hydroxymethylphenylglycine. This starting material is prepared byfirst reducing one of the aldehyde groups of 1,4-benzenedicarboxaldehydewith lithium tri(t-butoxy)-aluminum hydride, condensing the remainingaldehyde group of the resulting hydroxymethyl aldehyde with ammoniumcarbonate and sodium cyanide to give a hydantoin, and hydrolyzing thehydantoin with barium hydroxide.

Prior to acylation, it is desirable to protect the amino group on theglycine moiety with an easily removable protective group such ast-butoxycarbonyl, benzyloxycarbonyl, trichloroathoxycarbonyl, or similarprotective group commonly used in the synthesis of peptides. Thecarboxyl group can be activated for acylation by conversion to the acidchloride or to a mixed anhydride with, for example, a lower alkylchloroformate. It can also be activated by conversion to the2,4-dinitrophenyl or N-hydroxysuccinimidyl esters. If an ester of thecarboxyl group on the cephalosporin nucleus is used as an acylationsubstrate, e.g. a benzhydryl, t-butyl, trichloroethyl, or benzyl ester,the amine-protected phenylglycine can be coupled directly to the 7-aminogroup by using a carbodiimide such as dicyclohexylcarbodiimide.Alternatively, the protected phenylglycine can be activated forcondensation by reacting it first with carbonyl diimidazole or itsequivalent.

Following the acylation, the protective groups can be removed with anacid such as trifluoroacetic acid. The resulting salt is converted tothe zwitterionic product by means of a basic ion exchange resin such aspolystyrene-amine ion exchange resin (Amberlite IR-45) or else bybasification of an aqueous solution of the salt.

The compounds of formula I in which A is heterocyclic thio may also beprepared by first acylating 7-aminocephalosporanic acid (the compound offormula II in which A is acetoxy) with p-hydroxymethylphenylglycine andthen displacing the acetoxy group with a heterocyclic thiol according toknown methods. The compounds of formula I where R is methoxy ormethylthio may also be prepared by first acylating7-aminocephalosporanic acid and then inserting the methoxy or methylthiogroup by known methods.

The starting materials for the products of the invention, i.e. thecompounds of formula II, are either known or are prepared by knownmethods, including displacement of the acetoxy group of7-aminocephalosporanic acid with a heterocyclic thiol, also by knownmethods.

The compounds of the invention are highly active as antibacterialagents. They are formulated into injectable and oral dosage formulationssuch as solutions, suspensions, tablets, and capsules in the same manneras are other cephalosporin antibiotics and are administered by injectionor orally to prevent and treat bacterial infections. The doses will varywith the age, weight, and condition of the subject and are determinableby those skilled in the art based on data presented herein andexperience with other cephalosporins.

Data for a number of compounds of the invention follow:

    ______________________________________                                        COMPOUND IDENTIFICATION                                                       No.           A                                                               ______________________________________                                        47216         H                                                               37316         OCOCH.sub.3                                                     62516                                                                                        ##STR1##                                                       43026                                                                                        ##STR2##                                                       76026                                                                                        ##STR3##                                                       ______________________________________                                    

    __________________________________________________________________________    MIC/μg/ml                                                                  Compound No.                                                                           S. aureus                                                                          S. aureus                                                                           Strep. faecalis                                                                        E. coli                                                                            E. coli                                                                            Klebs. pneumo.                                                                        Klebs. pneumo.                 __________________________________________________________________________    47216   6.3   25             25   50   25      25                             37316   12.5  6.3   200      12.5 25   3.1     25                                                          200  50   25      25                             62516   25    12.5  200      25   25   12.5    12.5                                   3.1   6.3   100      12.5   12.5                                                                             6.3     6.3                            43026   12.5  3.1   200      12.5   12.5                                                                             12.5    12.5                           76026   50    50    >200     25   50   25      25                             __________________________________________________________________________

    __________________________________________________________________________    MIC/μg/me                                                                  Compound No.                                                                          Pseudomonas sp.                                                                        Salmonella                                                                          Shigella                                                                           Entero. aerog.                                                                        Serratia marc.                                                                        Staph. Villaluz                   __________________________________________________________________________    47216   >200     25    25   50      >200    200                               37316   >200     12.5  6.3  25      >200    100                                       >200     25    25   200     >200    100                               62516            12.5  12.5 50      >200    200                                       >200     3.1   6.3  25      >200     50                               43026   >200     6.3   6.3  25      >200     50                               76026   >200     25    25   50      >200    200                               __________________________________________________________________________

    ______________________________________                                        ED.sub.50 (mg/kg.)                                                            Compound                                                                              E. coli         Klebs. pneume.                                        No.     s.c.      p.o.      s.c.    p.o.                                      ______________________________________                                        47216   33        29        >50     50                                        37316   8.7       >50       20      >50                                       62516   17, 25    39, 46    12.5, 17                                                                              18, 14.5                                  43026   11, 11.2  7.4, 21   14.5, 7.2                                                                             8.3, 6.2                                  76026   8         25        9.5, 7  16.7, <12.5                               ______________________________________                                    

Due to the presence of both an amine group and a carboxylic acid groupin the product compounds of the invention, it is possible to prepareboth acid and base salts as well as zwitterionic forms of the compounds.Salts when obtained are readily converted to the zwitterions by knownmethods. The zwitterions in turn are readily converted into conventionalacid and basic salts. It is understood that all these salts are includedwithin the scope of the invention.

It is recognized that, due to the asymmetric α-carbonatom in the7-acetamido group, optical isomers will exist. While the D-isomer ispreferred, the L-isomer and the racemic mixtures are also within thescope of the invention. The isomers are obtained from racemic mixturesby conventional resolution techniques supplied to the intermediate sidechain before acylation or the final product.

The following examples are intended to illustrate the products andprocesses of the invention, but are not to be contrued as limiting thescope thereof. Temperatures are in degrees Centigrade unless otherwisestated.

EXAMPLE 17β-(DL-α-Amino-p-hydroxymethylphenylacetamido)desacetoxycephalosporanicacid

To a solution of 1,4-benzenedicarboxaldehyde (50.0 g., 0.373 mole) in200 ml. of dry tetrahydrofuran under nitrogen in an ice bath was addeddropwise lithiun tri(t-butoxy)aluminum hydride (104.0 g., 0.410 mole)dissolved in 500 ml. of dry tetrahydrofuran. After stirring for one halfhour in an ice bath, the reaction mixture was poured into 2 l. of icecold 2N hydrochloric acid. The aqueous solution was extracted with four800 ml portions of ether. The combined ether layers were washed with mlof ice cold 5% sodium bicarbonate solution and then with 500 ml ofsaturated sodium chloride solution. After drying, the ether was removedunder reduced pressure to give 46 g. of crudep-hydroxymethylbenzaldehyde. The crude product was chromatographed over1 kg of neutral alumina and the fractions eluted with ether andconcentrated. Upon cooling there crystallized outp-hydroxymethylbenzaldehyde (17.6 g., 35% yield), m.p. 44.5°-45°∝C.

To a stirred mixture of Phydroxymethylbenzaldehyde (10.0g, 0.0735 mole)and ammonium carbonate (17.1g, 0.15 mole) in 110 ml of 60% ethanolheated to 50° C there was added dropwise sodium cyanide (4.0g., 0.081mole) dissolved in 10 ml water. The mixture was stirred and heated to55°-60° C for 3 hours and then the temperature raised to 85° C for 1hour. After cooling in an icebath, the pH of the solution was brought to6 by the addition of concentrated hydrochloric acid. Upon overnightcooling, the solid which had precipitated was filtered, washed with coldwater, and dried. The 5-(p-hydroxymethylphenyl)hydantoin (11.0g., 72%yield), m.p. 189°-196° (dec.), was used to prepare the amino acidwithout further purification.

A mixture of 5-(p-hydroxymethylphenyl) hydantoin (10.9 g., 0.053 mole)and barium hydroxide (8 H₂ O) (25.5 g, 0.081 mole) in 125 ml water wasstirred and refluxed for 18 hours. After cooling in an ice bath thereaction mixture was diluted with 125 ml water. The solution wasacidified with concentrated sulfuric acid to pH 1, the barium sulfatefiltered, and the pH of the filtrate brought to 6 with lead carbonate.After filtration of the lead sulfate, the filtrate was saturated withhydrogen sulfide and the lead sulfide filtered. The aqueous solution wasthen concentrated to 100 ml by azeotroping with ethanol under reducedpressure. After cooling, there was precipitatedp-hydroxymethylphenylglycine (5.2 g., 54% yield) m.p. 228°-229° C (dec).After recrystallization from ethanol-water the compound had m.p.230°-231° (dec.)

Calc'd for C₉ H₁₁ NO₃ : C, 59.66; H, 6.12; N, 7.73. Found: C, 59.46; H,6.24; N, 7.93.

To a solution of p-hydroxymethylphenylglycine (8.0 g, 0.044 mole) andtriethylamine (8.8 g., 0.087 mole) in 160 ml water was addedt-butoxycarbonyl azide (6.95 g., 0.049 mole) dissolved in 120 mltetrahydrofuran. After stirring overnight at room temperature, thereaction mixture was washed twice with 200 ml. portions of ether. Theaqueous layer was covered with ether and in an ice bath was acidified topH 3-3.5 with 3N hydrochloric acid. The acidic solution was extractedthree times with 200 ml portions of ether. The combined ether layerswere washed with saturated sodium chloride solution, dried, and theether evaporated under reduced pressure. The resulting oil wastriturated with chloroform-hexane and the solid filtered off to giveN-t-butoxycarbonyl-p-hydroxymethylphenylglycine (7.74 g, 63% yield),m.p. 139°-141.5° (dec.).

Calc'd for C₁₄ H₁₉ NO₅ : C, 59.78; H, 6.81; N, 4.98. Found: C, 59.67; H,6.76; N, 4.69.

d1-N-t-Butoxycarbonyl-p-hydroxymethylphenylglycine (7.560 g., 0.0269mole) and quinine (10.199 g, 0.0269 mole) were mixed and dissolved in110 ml of boiling ethanol. The solution was allowed to cool to roomtemperature and to crystallize overnight. The salt was filtered off andthe crystallisation repeated three times.

The salt (17.76 g, m.p. 198°-201° dec., [α]_(D) ²⁵ -149.8, C=1, CH₃ OH)gave after three recrystallizations resolved salt (4.6 g, m.p. 205°-6°dec., [α]_(D) ²⁵ -163.4, C=1, CH₃ OH). An additional recrystallizationdid not increase the optical rotation.

The (-) quinine salt of (-)N-t-butoxycarbonyl-p-hydroxymethylphenylglycine was suspended in 75 ml.water and 175 ml ether in an ice bath and 3N hydrochloric acid added topH 2.5. The ether layer was removed and the aqueous layer extractedtwice with 100 ml portions of ether. The combined ether layers werewashed with 100 ml saturated sodium chloride, dried, and the etherremoved under reduced pressure. The residue was triturated withchloroform-hexane and filtered to give D (-)N-t-butoxycarbonyl-p-hydroxymethylphenylglycine (1.68 g, 98% recovery),m.p. 111°-113.5° dec., [α]_(D) ²⁵ = -136.5 (C=1, CH₃ OH).

To a solution of d1-N-t-butoxycarbonyl-p-hydroxymethylphenylglycine (3.0g, 0.011 mole) and N-hydroxysuccinimide (1.25 g., 0.011 mole) in 10 mldry tetrahydrofuran and 50 ml dry acetonitrile was added N,N'-dicyclohexylcarbodiimide (2.238 g., 0.011 mole). The mixture wasstirred at room temperature overnight. The dicyclohexylurea was filteredoff and the filtrate taken to dryness under reduced pressure. Theresulting solid was triturated with ether and filtered to give theN-hydroxysuccinimide ester of N-t-butoxycarbonyl-p-hydroxyphenylglycine(3.4 g., 83% yield) m.p. 141°-148° dec.

When D(-)-N-t-bitoxycarbonyl-p-hydroxymethylphenylglycine was used, thecorresponding optically active ester was obtained: m.p. 86°-90° dec;[α]_(D) ²⁵ = -47.6 (C 1, MeOH).

N, N'-dicyclohexylcarbodiimide (0.363 g., 1.76 mmole) was added withsitrring to a solution ofN-t-butoxycarbonyl-p-hydroxymethylphenylglycine (0.452 g, 1.61 mmole)and 7-aminodesacetoxycephalosporanic acid, t-butyl ester (0.434 g, 1.61mmole) in 5 ml tetrahydrofuran and 5 ml acetonitrile at 0° C. Thereaction mixture was warmed to room temperature and stirred overnight.Methylene chloride (10 ml) was added to the mixture and theN,N'-dicyclohexylurea was filtered off and washed with methylenechloride. The filtrate was washed with ice cold 1% phosphoric acid, withice cold 1% sodium bicarbonate and then with saturated sodium chloridesolution. The dried filtrate was chromatographed over silica gel, andthe fractions eluted with methylene chloride-ethyl acetate were combinedand taken to dryness. The residue was triturated with ether and filteredto give7β-(DL-α-N-t-butoxycarbonylamino-p-hydroxymethyl-phenylacetamido)desacetoxycephalosporanicacid, t-butyl ester (0.638 g, 75% yield), m.p. 126°-130° dec.

Calc'd for C₂₆ H₃₅ N₃ O₇ S.1/2H₂ O: C, 57.55; H, 6.69; N, 7.74. Found:C, 57.96; H, 6.45; N, 7.89.

To a solution of 7 ml trifluoroacetic acid containing 8 drops of anisoleat 0° C was added7β-(DL-α-N-t-butoxycarbonylamino-p-hydroxymethylphenylacetamido)desacetoxycephalosporanicacid, t-butyl ester (0.628 g., 1.2 mmole). The solution was stirred andmaintained at 0° C for 1 hour. The trifluoroacetic acid was removedunder reduced pressure and the residue triturated four times with ether.There was obtained7β-(DL-α-amino-p-hydroxymethylphenylacetamido)desacetoxycephalosporanicacid, trifluoroacetate salt (0.51 g., 90% yield), m.p. 141°-170° C dec.Calc'd. for C₁₉ F₃ H₂₀ N₂ O₇ S.1H₂ O: C, 44.79; H, 4.35; N, 8.25. Found:C, 44.97; H, 4.10; N, 8.02.

This salt is converted to the zwitterion by dissolving it in water andadding a polystyrene-amine ion exchange resin such as Amberlite IR-45.After stirring for about an hour at room temperature, the resin isfiltered off and the aqueous solution lyophilized to give the titlecompound.

The trifluoroacetate salt can also be dissolved in water, methylisobutyl ketone added, and tributylamine added to precipitate thezwitterion. The product is collected, washed, and dried.

EXAMPLE 2 7β-(DL-α-amino-p-hydroxymethylphenylacetamido)cephalosporanicacid

N-t-butoxycarbonyl-p-hydroxymethylphenylglycine (0.60 g, 2.14 mmole),7-aminocephalosporanic acid, t-butyl ester (0.705 g, 2.14 mmole) andN,N'-dicyclohexylcarbodiimide (0.485 g, 2.35 mmole) were reacted underthe same conditions as in Example 1. After two chromatographies oversilica gel and trituration with hexane there was obtained7β-(DL-α-N-t-butoxycarbonylamino-p-hydroxymethylphenylacetamido)cephalosporanicacid, t-butyl ester (0.238 g, 19% yield) m.p. 111°-115° dec.

Calc'd. for C₂₈ H₃₇ N₃ O₉ S: C, 56.84; H, 6.30; N, 7.10 Found: C, 57.65;H, 6.68; N, 6.71.

As in Example 1,7β-(DL-α-N-t-butoxycarbonylamino-p-hydroxymethylphenylacetamido)cephalosporanicacid, t-butyl ester (0.222 g, 0.376 mmole) was added to ice coldtrifluoroacetic acid and anisole. There was obtained7β-(DL-α-amino-p-hydroxymethylphenylacetamido)cephalosporanic acid,trifluoroacetate salt (0.159 g., 77% yield) m.p. 136°-150° dec.

Calc'd. for C₂₁ F₃ H₂₂ N₃ O₉ S.1/2 mole H₂ O: C, 46.16; H, 4.15; N,7.52. Found: C, 45.01; H, 3.95; N, 7.19.

The trifluoroacetate salt is converted to the title product as describedin Example 1.

EXAMPLE 33-(1,2,3-Triazol-5-ylthiomethyl)-7β-(DL-α-amino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid

3-(1,2,3-Triazol-5-ylthiomethyl)-7-amino-3-cephem-4-carboxylic acid(0.60 g., 1.92 mmole) was dissolved with stirring in 12 ml dry pyridinecontaining triethylamine (0.39 g, 3.84 mmole) and to the solution wasadded the N-hydroxysuccinimide ester ofN-t-butoxycarbonyl-p-hydroxymethylphenylglycine (0.73 g., 1.92 mmole).After stirring at room temperature for 4 hours, the reaction mixture waspoured into 200 ml of ether and the precipitated solid filtered. Thesolid was dissolved in 100 ml of water and the water covered with ethylacetate. This mixture was placed in an ice bath and acidified with 3Nhydrochloric acid to pH2. Any solid was filtered off and the ethylacetate layer removed and the aqueous layer extracted two times withethyl acetate. The combined ethyl acetate layers were washed withsaturated sodium chloride solution, dried, and the ethyl acetate wasremoved under reduced pressure. The residue was triturated with ether togive3-(1,2,3-triazol-5-ylthiomethyl)-7β-(DL-α-N-t-butoxycarbonylamino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylic acid (0.651 g, 59% yield) m.p.197°-220° dec.

Calc'd. for C₂₄ H₂₈ N₆ O₇ S₂.1/2 C₄ H_(10C), 50.89; H, 5.42; N, 13.69.Found: C, 50.83; H, 5.69; N, 12.04.

When the resolved D(-) phenylglycine derivative was used, the producthad m.p. 173°-198° dec.

3-(1,2,3-Triazol-5-ylthiomethyl)-7β-(DL-α-N-t-butoxycarbonylamino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid (0.570 g, 0.99 mmole) was added to 10 ml trifluoroacetic acidcontaining 2 ml anisole in an ice bath. The solution was stirred at 0°C. for one-half hour. The trifluoroacetic acid was removed under reducedpressure. The residue was triturated four times with ether to yield3-(1,2,3-triazol-5-ylthiomethyl)-7β-(DL-α-amino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid, trifluoroacetate (0.44 g, 75% yield) m.p. 155°-162° dec.

Calc'd. for C₂₁ F₃ H₂₁ N₆ O₇ S₂ : C, 42.71; H, 3.58; N, 14.23. Found: C,42.03; H, 3.67; N, 11.85.

When the pure diastereoisomer was used, the product obtained had m.p.164°-170° dec.; [α]_(C) ²⁵ = -13.1 (C 1, MeOH)

Analysis: C₂₁ F₃ H₂₁ N₆ O₇ S₂. 1 mole Et₂ O. Calc'd. for C, 45.18; H,4.66; N, 12.65. Found: C, 45.33; H, 4.73; N, 11.26.

The salts are converted to their zwitterions as in Example 1.

EXAMPLE 43-(2-Methyl-1,3,4-thiadiazol-5-ylthiomethyl)-7β-(DL-α-amino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid

3-(2-Methyl-1,3,4-thiadiazolyl-5-thiomethyl)-7-amino-3-cephem-4-carboxylicacid (0.695 g, 2 mmole), the N-hydroxy succinimide ester ofDL-N-t-butoxycarbonyl-p-hydroxymethylphenylglycine (0.760 g, 2 mmole)and triethylamine (0.41 g, 4 mmole) were reacted under the sameconditions as in Example 3. After evaporation of the ethyl acetate theresidue was triturated with hexane to yield3-(2-methyl-1,3,4-thiadiazola-5-ylthiomethyl)-7β-(DL-α-N-t-butoxycarbonylamino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid (0.709 g, 59% yield) m.p. 129°-138° dec.

Calc'd. for C₂₅ H₂₉ N₅ O₇ S₃.1 mole EtOAc: C, 50.07; H, 5.32; N, 10.07.Found: C, 50.43; H, 5.46; N, 10.42.

3-(2-Methyl-1,3,4-thiadiazol-5-ylthiomethyl)-7β-(Dl-α-N-t-butoxycarbonylamino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid (0.659 g, 1.1 mmole) was converted under the reaction conditions ofExample 3 to3-(2-methyl-1,3,4-thiadiazol-5-ylthiomethyl)-7β-(DL-α-amino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid trifluoroacetate (0.574 g, 85% yield) m.p. 142°-154° dec.)

Calc'd for C₂₂ F₃ H₂₂ N₅ O₇.1/2 mole H₂ O.1/2 mole Et₂ O: C, 43.11; H,4.34; N, 10.47. Found: C, 42.92; H, 4.07; N, 9.96.

The salt is converted to the zwitterion as in Example 1.

EXAMPLE 53-(1-Methyltetrazol-5-ylthiomethyl)-7β-(Dl-α-N-t-butoxycarbonylamino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid

3-(1-Methyltetrazol-5-ylthiomethyl)-7-amino-3-cephem-4-carboxylic acid(1.22 g, 3.7 mmole), the N-hydroxysuccinimide ester ofDL-N-t-butoxycarbonyl-p-hydroxymethylphenylglycine (1.40 g., 3.7 mmole)and triethylamine (0.75 g, 7.4 mmole) were reacted under the sameconditions as in Example 3. After trituration with hexane, there wasobtained3-(1-methyltetrazol-5-ylthiomethyl)-7β-(DL-α-N-t-butoxycarbonylamino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid (1.3 g, 59% yield) m.p. 138°-148° dec.

Calc'd. for C₂₄ H₂₉ N₇ O₇ S₂.1 1/2 mole EtOAc: C, 49.79; H, 5.67; N,13,55. Found: C, 49.75; H, 5.78; N, 13.30.

3-(1-Methyltetrazol-5-ylthiomethyl)-7β-(DL-α-N-t-butoxycarbonylamino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid was converted under the conditions of Example 3 to3-(1-methyltetrazol-5-ylthiomethyl)-7β-(DL-α-amino-p-hydroxymethylphenylacetamido)-3-cephem-4-carboxylicacid, trifluoroacetate salt (0.946 g, 71% yield) mp 158°-165° dec.

Calc'd for C₂₁ F₃ H₂₂ N₇ O₇ S₂. 2 mole H₂ O2 mole Et₂ O: C, 44.10; H,5.36; N, 12.41. Found: C, 43.95; H, 4.65; N, 12.40.

The salt is converted to the zwitterion as in Example 1.

EXAMPLE 6

When the following 7-aminocephalosporin compounds are acylated accordingto the procedures of Examples 1-5, the corresponding7-(α-amino-p-hydroxymethylphenylacetamido)cephalosporin compounds areobtained.

7-amino-3-(5-methyl-1,2,4-triazol-3-ylthiomethyl)-3-cephem-4-carboxylicacid

7-amino-3-(1-methyl-1,2,3-triazol-5-ylthiomethyl)-3-cephem-4-carboxylicacid

7-amino-3-(4-methyl-1,2,3 -triazol-5-ylthiomethyl)-3-cephem-4-carboxylicacid

7-amino-3-(tetrazol-5-ylthiomethyl)-3-cephem-carboxylic acid

7-amino-3-(2-methyl-1,3,4-oxadiazol-5-ylthiomethyl)-3-cephem-4-carboxylicacid

7-amino-3-(1,2,4-triazol-3-ylthiomethyl)-3-cephem-4-carboxylic acid

7-amino-3-methylthiomethyl-3-cephem-4-carboxylic acid

7-amino-3-methoxymethyl-3-cephem-4-carboxylic acid

EXAMPLE 7

For parenteral administration a pharmaceutical composition can beprepared by dissolving 500 mg. of sodium7-(α-amino-p-hydroxymethylphenylacetamido)-3-(1,2,3-triazol-5-ylthiomethyl)-3-cephem-4-carboxylicacid in 2 ml. of sterile water or normal saline solution. Any of theother products disclosed herein may be formulated similarly,particularly the products of examples 1, 2, 4, and 5.

EXAMPLE 8

A capsule for oral administration may be prepared by mixing 500 mg. of acephalosporin disclosed herein, product, particularly a product ofexamples 1-5, 250 mg. of lactose, and 75 mg. of magnesium stearate.

We claim:
 1. A compound of the formula ##SPC3##wherein A is acetoxy orhydrogen, or a pharmaceutically acceptable salt thereof.
 2. A compoundas claimed in claim 1, being7-(α-amino-p-hydroxymethylphenylacetamido)-3-desacetoxycephalosporanicacid.
 3. A compound as claimed in claim 1, being7-(α-amino-p-hydroxymethylphenylacetamido)cephalosporanic acid.